Which of the Following Is a Major Difference Between the Chondrichthyans

Which of the following is a major difference between the chondrichthyans and the ray-finned fishes?

A) Only chondrichthyans have a lung or swim bladder.
B) Chondrichthyans have a cartilaginous skeleton, whereas ray-finned fishes have a bony skeleton.
C) Only ray-finned fishes have paired fins.
D) Chondrichthyans evolved in fresh water, whereas ray-finned fishes evolved in salt water.
E) Only chondrichthyans have true jaws.